Halogenosilahydrocarbons and their production



Patented May 16,1950

HALOGENOSILAHYDROCARBONS AND V I THEIR- PRODUCTION John T. Goodwin, Jr., Midland, 'Mich., assignor to Dow Corning Corporation, Midland, Mich., a ,corporation of Michigan No Drawing. Application March 19, 1949, Serial No. 82,475 v 9Clai1ns'. (Cl. 260-4482) The present invention relates to new organosilicon compositions, and to their methods of production; Th present organosilicon industry, is based upon siloxanes which are materials in which the silicon atoms are linked through oxygen atoms. Another type of compoundis one in which the siliconatoms are linked directly to each other. Still a. third type is one in which the silicon atoms are linked by organic radicals. The literature presents very little information about this last type of compound.

Objects of the present invention; are to produce organosilicon compounds in which th silicon atoms are linked b methylene radicals. Other objects and advantages of the present invention will be apparent fromthe following description, and the subjoined claims.

The compounds hereof are'of the type where each X represents a halogen atom, each R. represents a radical of the group consisting of alkyl and monocyclic aryl radicals and n represents an integer from lto 2 inclusive. Thus, each R may be an alkyl radical as from methyl to octadecyl or a monocyclic aryl radical such as pheny1 or tolyl. Specific type compounds in accord herewith are of the formulae RaSiCHzSiXa and [RaSiCHalzSiXa The compounds in accord herewith are produced by reacting a compound of the type SiX4, wher each X represents a halogen atom with a reagent of the group consisting of RsSiCHzMgX and R3-SiCI-I2Li where each R represents a radical of the group consisting of alkyl and monocyclic aryl radicals.

The organolithium compound, RsSiCHzLi may be prepared by gradually adding RsSiCHzX to a finely divided suspension of lithium in mineral oil.

The Grignard reagent, RaSiCHzMgX, may be prepared by reacting magnesium with chloromethyltrimethylsilane.

To assure a high yield of the desired product, RaSiCmSiXa the organometallic compound is employed in proportion of 0.5 to less than 3 molar equivalents per mol of silicon tetrahalide. Preferably equimolecular amounts are employed. When a low ratio of silicon tetrachloride to the other reactant is employed disubstitution is obtained. There are thereby produced compounds of the type [(CH3)3SiCH2]2SiCl2.' This compound may be hydrolyzed and the hydrolyzate copolymerized with octamethylcyclotetrasiloxane to produce fluids having a low pour point for such purposes as hydraulic fluids. The reaction in accord herewith may be carried out by mixing the reagent of the'group consisting of R3SiCH2Li and RaSiCHzMgX with the silicon tetrahalide compound. The resulting product may be purifled by filtering and distilling if desired.

The products hereof ar of substantial utility as intermediates in the production of other organosilicon compositions. The products hereof are of utility in the production of soluble siloxane polymers which may be thermallyset to resinous solids. Thus, the compounds of the present invention may be hydrolyzed and condensed alone to produce such resins. Also, the compounds of the present invention may be hydrolyzed and condensed in mixture withfother organosilicon chlorides to produce organosiloxanes. When cohyclrolyzed and condensed "with a triorganosilicon halide stable fluids are obtained. When hydrolyzed with a mono or diorgano-silicon halide, siloxanes are obtained which may be condensed to resinous solids. These resins are of utility in formulating heat and weather resistant coatings for boilers, stacks,

ovens, and other hot metal surfaces.

The following examples illustrate the methods of the present invention.

Example 1 (CHzOaSiCHzMgCl was prepared by reacting 245 parts by weight of (CH3)3SiCH2Cl with 48 parts of magnesium in ethyl ether. The Grignard reagent so prepared was reacted with 680 parts of silicon tetrachloride by pouring it into 'SiCh. The reactants coupled readily at room temperature. The coupled product wasfiltered. and the filtrate transferred to the stripping still. Th ether was stripped off. Distillation yielded 255 parts of the compound (CHa)3SiCH2SiC13 in a yield of 64.7 percent. The compound had a boiling point of 165.8 C. at atmospheric pressure, a density of 1.1234 at 25 C., a refractive index of 1.4448 at 25 C., and a specific refraction of 0.2368.

When a mixture of 149.5 parts of CHaSiCla, 221.5 parts of (CI-1:):S1CI-IzSiCla and 191 parts of 'CcHsCHaSiClz is gradually added during onehalf hour to 635 parts of toluene in 1168 parts of H20, hydrolysis occurs with the separation 01 a water insoluble layer. This organic layer is then separated and shaken with NaHCOa. It is then washed, filtered, and concentrated to 35% solids. The resulting composition will be upon drying a tough, flexible resin.

Example 2 l 2. Compositions in accordance with claim 1 in whefi smcdfi tetracmmde in amdfint 6f m l g fi l c fi 'e with claim 1 in parts by weight is gradually added over a period p 1 f th if one hour to 84 parts of the organolithium comwhich F represents a 0 8 group ground (cm zsicrnm dissolved mpentane cou- 5 methyl and phe-mtrildic-als and "f t a '5. ill TS iQQ JQ QmQFE iF Ei I ii Win Phen' pling occurswith the pigoduction of $21? radialgf V a s (CI-IaMSiCHzSiCla. 7; 4. Compositions in accord with claim 1 in When 775.3 parts of this product is mixed with Winch is equal to P 971.8 parts of CHaSiClz, addext-to. Isl-m ment- 1 with claim 1 in toluene, and the resulting solution addediato-fiiafl 5 equal to parts of H20 in 270 parts oi is opropyl.aicohohhgdrolysis occurs with phase sebaratiom e reaction mixture is decanted. The water insoluble; layer is refluxed for 2 hours and then washed. It is then concentrated to 35% solids. re- .-R3s1cH2M x 2:2 :5 ig g upon drying Wm be a tough: a and Ig S iQl-hm where each R represents a radical Example 3 ofithe-group consisting pf alkyl and monocyclic 20 aryl radicals and X represents a halogen atom, v partsetby weight; of ma nesium-iamtzfiflfisnfifll w1m a-tcom w of the -type son, therebeing or ther '.-wene.rmixed; and 239, 9 "12.512135 :of 1 present at least :mS-sntI-iIeSs, than -3- mols of the QelisiGHflzSiGHzGlzadded 110,.thermixi1ura; 71940 former per mol of the latter, whereby a product pa, ts; f ;,-ethy1-. ether weiterthenzq-addedaand t ofthe formula tRaSiGHQhsixgnfwherelmis' an tum-stirred.'sThe:r s t firi nandim 25 integer from t t' z'rinclusive-gis"obtainedi" z vlisiflfiazsi HzM Cl- 92-"I he-= method"=fl inaccordarice witlr claim- -la in 1000 pan ssofs toluene: art-11111500,; nari:;s ot:S1614 wfiieheach Rnepreseritsi-methy-l. weregmixcdeandztheiG zignard:reagent: dem 600mm, Jit.

index 'j $1.511; ates? ,g,\a ;de s1ta $3 o QTHE TR EEBE CES:

' Sommer, Jourmhm che m, 800., vol. 69

(1947), page 980"."

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1. COMPOSITIONS OF THE FORMULA 